Corrects 200+ instances of "it's" where it should've been "its" instead (#85169)

## About The Pull Request

it's - conjunction of "it" and "is"
its - possessive form of "it"

grammar is hard, and there were a lot of places where "it's" was used
where it shouldn't have been. i went and painstakingly searched the
entire repository for these instances, spending a few hours on it. i
completely ignored the changelog archive, and i may have missed some
outliers. most player-facing ones should be corrected, though
## Why It's Good For The Game
proper grammar is good

## Changelog
🆑
spellcheck: Numerous instances of "it's" have been properly replaced
with "its"
/🆑

code/datums/eigenstate.dm

@@ -25,7 +25,7 @@ GLOBAL_DATUM_INIT(eigenstate_manager, /datum/eigenstate_manager, new)
 			targets -= target
 			continue
 		if(!subtle)
-			target.visible_message("[target] fizzes, collapsing it's unique wavefunction into the others!") //If we're in a eigenlink all on our own and are open to new friends
+			target.visible_message("[target] fizzes, collapsing its unique wavefunction into the others!") //If we're in a eigenlink all on our own and are open to new friends
 		remove_eigen_entry(target) //clearup for new stuff
 	//Do we still have targets?
 	if(!length(targets))